Introduce AbstractParallelEvaluator

This change enables alternate evaluation strategies.

Drive-by fix to GraphTester, making TestFunction static because it has
no dependencies on its outer class, and adding #unsetConstantValue.

RELNOTES: None.
PiperOrigin-RevId: 164327055

1 files changed, 7 insertions, 4 deletions

diff --git a/src/test/java/com/google/devtools/build/skyframe/GraphTester.java b/src/test/java/com/google/devtools/build/skyframe/GraphTester.java
index 75ebadf4c9..384a87928c 100644
--- a/src/test/java/com/google/devtools/build/skyframe/GraphTester.java
+++ b/src/test/java/com/google/devtools/build/skyframe/GraphTester.java
@@ -164,10 +164,8 @@ public class GraphTester {
     return LegacySkyKey.create(NODE_TYPE, key);
   }
 
-  /**
-   * A value in the testing graph that is constructed in the tester.
-   */
-  public class TestFunction {
+  /** A value in the testing graph that is constructed in the tester. */
+  public static class TestFunction {
     // TODO(bazel-team): We could use a multiset here to simulate multi-pass dependency discovery.
     private final Set<Pair<SkyKey, SkyValue>> deps = new LinkedHashSet<>();
     private SkyValue value;
@@ -216,6 +214,11 @@ public class GraphTester {
       return this;
     }
 
+    public TestFunction unsetConstantValue() {
+      this.value = null;
+      return this;
+    }
+
     public TestFunction setComputedValue(ValueComputer computer) {
       Preconditions.checkState(this.value == null);
       this.computer = computer;